BirdAnalyst
BBS Route · Colorado · BCR 18

Two Buttes Bird Survey Route

A standard 50-stop Breeding Bird Survey route. 71 species recorded across 34 survey years, still active.

71Species RecordedSpecies recordedDistinct species detected on standard-protocol BBS runs here across all years on record — a measure of survey breadth, not a complete checklist.Full methodology →
34Years SurveyedYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →
1973–2015Span
5Observers

Bird Species Found on Colorado Two Buttes

Top 40 of 71 species by most recent count. Each links to its species trend.

Species recorded on the Two Buttes route.
Recent countThe raw number of individuals recorded on this route in its most recent survey year. A single-route tally, not a trend.Full methodology →TrendPercent change in the route-weighted abundance index between a smoothed baseline window and the most recent one. It tracks direction, not absolute population.Full methodology →Baseline yearThe first year of the smoothed window the trend is measured from. An earlier baseline means a longer record stands behind the number.Full methodology →History
Lark BuntingPasserellidae1692015-74%1975
Horned LarkAlaudidae1302015-73%1975
Western MeadowlarkIcteridae892015-90%1975
Mourning DoveColumbidae802015-71%1975
European StarlingSturnidae332015+8%1977
Cliff SwallowHirundinidae282015+229%1993
Barn SwallowHirundinidae242015+371%1975
Cassin's SparrowPasserellidae172015-93%1975
Western KingbirdTyrannidae102015-83%1975
Eurasian Collared-DoveColumbidae102015+26%2012
Common GrackleIcteridae82015-15%1977
Northern MockingbirdMimidae72015-68%1975
Red-winged BlackbirdIcteridae62015-93%1975
Burrowing OwlStrigidae52015-56%1975
Chihuahuan RavenCorvidae52015-43%1975
Grasshopper SparrowPasserellidae52015-94%1975
Upland SandpiperScolopacidae51984-72%1975
Ring-necked PheasantPhasianidae42015-91%1975
Brewer's BlackbirdIcteridae42013+0%2005
Brown ThrasherMimidae41997+300%1984
Long-billed CurlewScolopacidae31994-94%1975
Swainson's HawkAccipitridae32015-60%1975
House SparrowPasseridae32015-88%1975
Bank SwallowHirundinidae31995+91%1984
Red-tailed HawkAccipitridae32012+50%1992
Yellow-headed BlackbirdIcteridae32008+0%1985
Vesper SparrowPasserellidae32012+0%2008
Northern HarrierAccipitridae22009+33%1978
Field SparrowPasserellidae21975n/an/a
Mountain PloverCharadriidae22015-53%1985
Scaled QuailOdontophoridae22014+67%1985
Orchard OrioleIcteridae21985+0%1981
Great Horned OwlStrigidae22015+40%1992
Brewer's SparrowPasserellidae22011-25%2005
MallardAnatidae22008+100%1997
KilldeerCharadriidae12015-81%1975
Northern BobwhiteOdontophoridae12009-83%1977
Rock PigeonColumbidae12014-74%1975
Yellow-billed CuckooCuculidae11982+0%1973
Common NighthawkCaprimulgidae12015-88%1978

Source: USGS North American Breeding Bird Survey, retrieved 2026-05-22. A route is a sample, not a census.